Speed Laws

All fifty states base their speed regulations on the Basic Speed Law. "No person shall drive a vehicle...at a speed greater than is reasonable or prudent...and in no event at a speed which endangers the safety of persons or property".

Under California law,

The maximum speed limit in an urban area is 55 mph.

All other speed limits are called prima facie limits, which are considered by law to be safe and prudent under normal conditions. Certain prima facie limits established by State law include:

The 25 mph speed limit in residential districts,

25 mph in school zones when children are present,

and the 15 mph speed limit in alleys, and at intersections and railroad crossings, where visibility is limited.

The above speed limits do not need to be posted to be enforced.

Speed limits between 25 and 55 mph must be established on the basis of traffic engineering surveys. These surveys include:

An analysis of roadway conditions, accident records, and a sampling of the prevailing speed of traffic.

A safe and reasonable limit is set at or below the speed at which 85% of average traffic moves.

Traffic flowing at a uniform speed improves safety through fewer accidents; i.e. Drivers are less impatient, pass less often, and tailgate less which reduces rear-end collisions. The posting of the appropriate speed limit simplifies the job of enforcement officers, since most of the traffic is voluntarily moving at the posted speed. Blatant speeders are easily spotted, safe drivers are not penalized, and traffic officers aren't asked to enforce unrealistic and arbitrary speed limits.

What can we do about speeding vehicles on my street?

Speed limits are often taken for granted until a problem arises, most people pay little attention to the theory behind them. Each year, the Traffic Engineering Division receives complaints of speeding on residential streets and/or alleys.

At the written request of a resident/property owner:

Staff will monitor the location and verify actual versus "perceived" speeds on a street.